Goodbye, UWB; but we hardly knew you

Ultrawideband (UWB) was supposed to be the "next big thing", but it's not there yet (and may never be); what happened?

You may have seen recent reports that ultrawideband (UWB) technology is having a tough time, "Report: Ultrawideband dies by 2013." Some of its IC proponents have folded or are in dire straits, and one analyst flatly states that it will be dead in a few years. At the same time, higher-speed and longer-range versions of Wi-Fi, such as WiMAX, seem to be getting traction, "Wi-Fi backers drive to 60 GHz."

I'll be the first to say that I don't place much stock in what the pundits say; they are no smarter than most, and have no better crystal ball than any of us, IMO. But there is no doubt that UWB is not getting industry support or design-ins as hoped for by its proponents.

Why is this? Again, pundits (including me) always have excellent rear-view vision, and it's all too easy to glibly explain what happened and why; if only our foresight were as accurate.

But my view is that UWB suffers from two problems: it's not clear what problem it solves that can't be solved by other, perhaps less expensive or difficult approaches; and it is largely a new standard rather than an extension of an existing one.

One thing that helps a new standard take hold, grow, and really insinuate itself into the industry's fabric and end-user's world is when it is an extension of an existing, successful standard. This means that successive, improved generations can be backward compatible, a big plus in the real world of products and consumers. IEEE 802.xxx and USB are good examples of this approach. Or consider the much more mundane, basic-landline telephone. This is a standard that has served us well for over 100 years, and nearly every new feature or enhancement (Touch-Tone in place of pulse dialing, Caller ID, Call Forwarding, Call Waiting) did not obsolete previous installations, but built on them with continuing support and compatibility at the phone company's central office and local loop.

A substantially new standard requires significant investment in infrastructure, design know-how, and user experience and acceptance. And while an existing standard eventually runs out of extensibility (in plain terms, it runs out of gas) and must be replaced or superseded (think IP-based phones replacing the older standard), it takes a compelling argument to make it happen.

Follow-up on last week's column: Many of you responded to last week's column "In recognition of the older discrete component" with you own list of components with great longevity, in addition to the 2N2222 transistor I cited. Among them were the 2N3055 (along with its companion, the MJE2955), BU208, BC547, BC548, uA741 op-amp or many of its derivatives, 1N4148, IN4007, LM555,2N2905 PNP, 2N2907 PNP, LM317 positive regulator, LM337 negative regulator, 2N7000 FET, 1N914 small-signal switching diode, 1N4000 series rectifier, 1N5817 Schottky, 6N137 optoisolators, LF411 JFET op amp, TL072 dual JFET op amp, and the CLC436 high-speed op amp. ♦

Teacher, Low power is the promise of UWB however WiMedia's implementation of UWB was by no means "Low Power" at 2 to 3 watts power consumption. (It takes a lot of power to operate those Giga Bits per second+ ADC's and DAC's along with the FEC and other baseband logic blocks) compared to some of the most recent WiFi chips at less than 300mW it's hard to claim WiMedia is "Low Power" with a straight face.

Answering your question what problem UWB radio technology can solve? Here one important point: MB-OFDM UWB technology requires 5-10 times less energy per transmitted bit than WiFi. That means that portable devices equipped with UWB will have a much longer battery life time. If one uses UWB as a means to transfer big amounts of data to/from the device we talk about 5-10 times longer battery life time related to the same amount of data. This is a breakthrough for any portable device storing audio, picture and video data and exchanging such data with other devices in a convenient wireless way! This advantage increases with the amount of data carried around - which increasing constantly - just look on the amount of memory available in todays portable devices (16GByte+). This explains, why leading companies for wireless connection of portable devices bet on UWB radio technology and will continue to do so regardless, what rumors are spread in the press. One more answer concerning data rate: If you add the WXP protocol on top of the UWB radio technology it gives you about 250-280 Mbps real user level TROUGHPUT (out of the 480 Mbps PHY burst data rate)at IP level. Devices are qualified for mass production and thus would be ideal to complement todays living room / office IP based communications enabling such high data rates with cheap and SMALL (just one antenna, or two if you add diversity), which at the end consume only 20% or less of the energy compared to other radio technologies available in mass production.

As the CTO of the oldest UWB company in the consumer electronics space I would like to point out that WiMedia's implementation of UWB failed, not UWB. UWB is a spectrum allocation not a specific implementation of the technology. Pulse-LINK's UWB technology does deliver on the promise of UWB with over 800 Mbps of application layer throughput delivered both wirelessly and over wire such as coax. We achieved this with a totally different architecture than WiMedia. Pulse-LINK's Cwave UWB solution is optimized to take advantage of the unique wide bandwidth characteristics of UWB. The solution attempted by WiMedia was based on fundamentally narrow band techniques that traded away almost all the reason one would do UWB to begin with.

OK, so this article hit the nail on the head, but is completely missing one important point - Wireless USB is based on UWB! Wireless USB is a simple extension to USB technology. The protocol and topology is completely re-used, so the billions of dollars of infrastructure investment is preserved. Wi-Fi and 60GHz do not have any of this infrastructure to leverage, at least not for Wireless PAN.

OK, so this article hit the nail on the head, but is completely missing one important point - Wireless USB is based on UWB! Wireless USB is a simple extension to USB technology. The protocol and topology is completely re-used, so the billions of dollars of infrastructure investment is preserved. Wi-Fi and 60GHz do not have any of this infrastructure to leverage, at least not for Wireless PAN.